Blog

When to Plant Rhubarb in Berks County, PA

Rhubarb is a long-lived perennial vegetable grown for its tart, colorful stalks. Only the stalks are edible as the leaves contain toxic oxalic acid.

Berks County, Pennsylvania is in USDA Zone 6b. The average last spring frost is April 21 and the first fall frost is October 24, giving you a growing season of approximately 186 days.

At an elevation of 877 feet, Berks County receives approximately 46.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Rhubarb during the growing season.

Berks County, PA (Zone 6b) Moderate season
186 days
Last Spring Frost April 21
186 growing days
First Fall Frost October 24

Berks County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: May 4
Recommended (50%) ✓ Fits season
Transplant: May 12
Safe Start (90%) ✓ Fits season
Transplant: May 31

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Rhubarb needs ~7,528 GDD — county provides 2,557 GDD May not mature

Rhubarb Planting Timeline โ€” Berks County, PA

Rhubarb Planting Calendar

Activity When Date Range
Transplant Outdoors May 12 May 12 โ€“ May 26

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Transplant Outdoors
June โ€”
July โ€”
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

365โ€“730 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6b

Growing Season

186 days

Growing Tips for Berks County

Plant crowns in early spring in rich, well-drained soil. Do not harvest stalks the first year. Pull (do not cut) stalks at harvest to avoid introducing rot.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Rhubarb in Berks County, PA?

Berks County is in Zone 6b with an average last frost of April 21. Plan your Rhubarb planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Berks County, PA?

Berks County, Pennsylvania is in USDA Hardiness Zone 6b. The average last spring frost is April 21 and first fall frost is October 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Berks County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Berks County, PA. Local conditions may vary. Last updated: April 2026.